In 2005 and 2006, Gregg learned firsthand the difficulty of utilizing the complex process. As chairman of the Budget Committee, the New Hampshire Republican tried to get $80 billion worth of Medicare savings over five years – less than 2 percent of Medicare spending.

Although the GOP controlled both houses of Congress and the White House, Gregg writes that he achieved just $40 billion in savings "because many Republicans did not want to vote for this spending restraint."

Even worse was "how President Obama and Democrats used reconciliation to pass Obamacare on Christmas Eve 2009," Gregg recounts. "They did this with a reconciliation instruction that called for a mere $1 billion in entitlement savings over 10 years. They then stuffed trillions of dollars of new programs into the bill while getting a Congressional Budget Office score that was fallacious."

This "was unquestionably the lowest point in the checkered history of the congressional budget process," he writes.

Gregg, who retired from the Senate in 2011, warns that, with 24 Republicans up for re-election in 2016, Democrats will claim that any budget and reconciliation bill passed by the Republican majority "cuts Medicare, Social Security, healthcare, college student aid, farm programs and veterans benefits."

It will be a "tough vote" for many Republican lawmakers, he says.

Republicans should also keep in mind that even if reconciliation passes on a party-line vote (which has historically taken place), Obama "will veto it and an override will fail."

He says the process "could turn into a brave but doomed charge of the light brigade."

Another danger is "the risk of overplaying your hand," Gregg writes. "One reason Obamacare has been so unpopular is because it was jammed through in a viciously partisan manner. The American people did not think it was fair."

Major policy changes on issues like taxes, Medicare, or Social Security "will be accepted only if they are fairly developed, considered and passed," he warns. "If reconciliation is used unfairly, Americans will be as disgusted with Republicans as they were with Democrats."

Gregg suggests that the GOP do something that has never been tried: reaching out to Democrats in an effort to pass a bipartisan reconciliation bill dealing with tax and Medicare reform.

Regarding Obamacare, "Republicans should take it on in pieces outside of reconciliation," according to Gregg. "This would give Republicans the high political ground on many votes."

If overplayed, reconciliation "becomes a game of Russian roulette with all the chambers loaded," he concludes. "A bipartisan reconciliation bill, however, has magic-bullet possibilities."